I. Field of the Invention
The present invention relates generally to a power bucket for use with a power shovel for loading and unloading cargo.
II. Description of the Prior Art
The previously known clam shell buckets of the type for use with power shovels typically comprise a air of bucket halves which are pivotally secured adjacent their upper end. The upper end of the bucket is also known as the bucket head and this head is connected by a cable to a power mechanism which lowers and raises the bucket. Additionally, the power shovel includes a closure cable to move the bucket halves between their open and their closed position.
Because of the construction of the previously known clam shell buckets, the clam shell buckets dig downwardly into the load as the clam shell bucket is moved from its open and to its closed position. Such buckets are effective for unloading deep cargo containers, such as the cargo area for a freighter containing aggregate material like coal, iron ore, or the like.
While these previously known clam shell buckets have proven effective for unloading cargo from deep cargo containers, they have not proven wholly effective for removing only a relatively shallow portion of the load. For example, in the event of an environmental spill on the bottom of a river bed or the like, it is desirable to remove only the contaminated area of the river bed which may extend only several inches into the river bed. Consequently, when these previously known clam shell buckets are used to remove such environmental spills, the clam shell buckets remove not only the contaminated portion of the bed, but also a large portion of the uncontaminated soil beneath the lake bed.
All of the removed material, however, must be disposed of which is not only time consuming, but also very expensive.